The vaginal microbiome in HIV positive and negative women sampled at two Chicago hospitals

HIV infection can cause immune deficiency and allow opportunistic infections, and, conversely, disruption of the normal human microbiota can be associated with inflammation, potentially promoting HIV transmission and replication. In this study we investigated the associations among HIV infection, the vaginal microbiota, and socioeconomic status by comparing vaginal microbiome samples from a large cohort (n=319) from two different US hospitals serving different socioeconomic groups. Within each hospital, we compared HIV+ and HIV- women. We found that rates of bacterial vaginosis, as measured by Nugent score, were higher in the hospital serving the less affluent community, and Nugent scores were also higher among HIV+ women. Higher Nugent scores correlated with higher bacterial diversity and lower colonization with Lactobacillus, as seen in previous studies. HIV status had only modest associations with microbiota measures-HIV+ status was weakly associated with increased diversity and increased proportions of pro-inflammatory genera. In previous work, some though not all comparative studies of vaginal microbiota sampled in US versus African hospitals have shown more extreme differences. Evidently effects of socioeconomic level or HIV infection status on women's health at the hospitals studied here were not great enough to result in large differences in the vaginal microbiota.